(New York) – An Israeli airstrike that killed 12 civilians – the largest number of civilians killed in a single attack during the Gaza fighting in November – was a clear violation of the laws of war.

On November 18, 2012, Israeli forces dropped what appears to have been a large aerial bomb on the three-story home of the Dalu family in Gaza City, killing 10 members of the household – one man, five women, and four children. A young man and an elderly woman of the Muzannar family next door were also killed.

At first the Israel Defense Forces (IDF) said they were attacking a Hamas fighter named Yahia Abayah. Eight days later the IDF said the target had been the man killed in the house, Mohamed Jamal al-Dalu, whom they called a “terror operative” for Hamas without providing supporting information. Even if al-Dalu, a low-ranking police officer, was a legitimate military target under the laws of war, the likelihood that the attack on a civilian home would have killed large numbers of civilians made it unlawfully disproportionate, Human Rights Watch said. Attacks in which the expected civilian loss exceeds the anticipated military gain are serious violations of the laws of war.

“The Israeli claim that the attack on the Dalu home was justified is unsupported by the facts,” said Fred Abrahams, special advisor at Human Rights Watch, who conducted research in Gaza. “The onus is on Israel to explain why it bombed a home full of civilians killing 12 people.”

The Israeli strike occurred around 2:30 p.m. in the residential and densely populated Nasser neighborhood of Gaza City. The head of the household, Jamal al-Dalu, a 50-year-old food distributor, told Human Rights Watch that he had gone to the market with his son Abdallah to buy food for his family, and then to the mosque for afternoon prayers. While Jamal al-Dalu was praying, his son received a telephone call that that their home had been destroyed and family members killed.

A relative, Ayman al-Dalu, said he heard the explosion and arrived at the house 10 minutes after the attack. “The whole building had collapsed,” he said. “Out front was nothing, only yellow sand. When we arrived we could see two bodies in the rubble.” Those were the bodies of Suhaila, 73, and Samah, 25, he said.

The sole survivor of the attack, 16-year-old Nasser Saluha, the brother of one of the victims, Samah al-Dalu, told Human Rights Watch that he had gone to the house to play with the other children and they were about to eat lunch in an upstairs room when the house was struck without any warning:

My sister was bringing the food for lunch and we were about to start. I thought that something hit the house strongly. I didn’t hear anything. I felt a shock and pressure and something was pulling me into the ground. I found myself lying on my back with dust and sand all over my body. I managed to get out of the rubble and run into the street. I felt pain in my leg; my whole body was cut up and needed stiches.

Nasser said that he was upstairs with his sister and the four children when the explosive hit. The women were downstairs and Mohamed al-Dalu, the only man in the house, was in a bedroom.

The family and civil defense forces dug out eight members of the family from the rubble that afternoon. The bodies of two victims – Yara, 17, and Mohamed, 29 – were not discovered until November 22.

The attack on Jamal al-Dalu’s home also killed a grandson and grandmother from the al-Muzanner family, who lived next door. The blast ripped open the back walls facing the Dalu home and caused major damage inside.

The head of the neighboring household, Mohamed al-Muzannar, owner of the Ramadan Muzannar sweets factory, told Human Rights Watch that he was in a front room on the other side from the Dalu house when the attack took place. The strike killed al-Muzannar’s son Abdallah, 18, a science student at al-Azhar University, and his mother Amina, 83. Mohamed’s wife Naha, 37, was injured in both legs.

One of Mohamed al-Muzannar’s sons, Amjad, a 20-year-old accounting student, said he was on the stairs of the two-story house at the time of the strike. “It was quiet, we had just heard a strike on the Danah building [about 700 meters away] about half an hour before,” he said. “Suddenly the ceramic tiles fell on me, so I knew it was in this area. I ran downstairs to get my parents and all of a sudden I couldn’t see, it was all smoke and dust. I tried calling [to my family] but I have asthma [so I couldn’t] and I ran into the street.”

Another son, 17-year-old Haitham, said he was on the back balcony facing the Dalu house at the time. “There was dust and I flew into the wall – I couldn’t see,” he said. “I could hear someone yelling, ‘Your brother is dead! Your brother is dead!” Haitham suffered cuts on his arm, chest, left ear, and back of the head, most of which required stiches.

On the staircase of the Muzannar house Human Rights Watch saw streaks of blood that Amjad and Haitham said came from their injuries as they groped their way through the dust and smoke out of the house.

In addition to the 12 deaths in the Dalu and Muzannar families, the airstrike wounded at least nine civilians in the area, and badly damaged or destroyed three other homes.

When Human Rights Watch visited the site one week after the strike, researchers found no remains of the Israeli munition, which family members said civil defense crews had removed while recovering the bodies. The complete destruction of the three-story house and the extensive damage to the surrounding homes suggests that Israeli forces dropped a large aerial bomb.

Israel has offered different explanations for what happened. Just after the attack, IDF spokesperson Lt. Col. Avital Liebovitch described the strike as an accident that Israel was “still looking into it.” She said the intended target had been a man “in charge of rocket launching.”

Another IDF spokesperson, Brig. Gen. Yoav Mordechai, said on television the day of the strike that the Israeli military had tried to target a senior member of Hamas’s armed wing, the al-Qassam Brigades, whom he identified as Yahia Abayah. “Although I don't know the outcome, there were civilians harmed by this,” he was reported as saying.

Members of the Dalu family and neighbors told Human Rights Watch they had not heard of anyone named Yahia Abayah. His name is not listed as a killed fighter on the official websites of Hamas’s al-Qassam Brigades or Islamic Jihad’s Saraya al-Quds.

On November 27, five days after Mohamed al-Dalu’s body was found, Lt. Col. Liebovitch said that the military had targeted Mohamed al-Dalu because he was a “known terror operative affiliated with the military wing of Hamas.” She provided no information to support the claim.

The IDF did not respond to a request from Human Rights Watch for more information.

Members of the Dalu family and neighbors interviewed separately said that Mohamed al-Dalu was not a member of any Palestinian armed group. He was a lieutenant in the civilian police under the Interior Ministry, they said, specializing in VIP protection.

The website of the al-Qassam Brigades regularly posts the names and biographies of its killed fighters, including 20 men from the eight days of fighting in November, but as of December 6 it had not posted any mention of Mohamed al-Dalu. At the site of the Dalu house, Human Rights Watch saw two posters, one from Hamas and one from the al-Israa Mosque, which called Mohamed al-Dalu a “martyr” and “fighter” for the al-Qassam Brigade and showed him respectively with an assault rifle and a pistol. The family and Palestinian journalists in Gaza said this was common for killed police and employees of the government, especially if Hamas covered the costs of the funeral.

Mohamed al-Dalu’s commander in the police, Maj. Refa’at al-Wali, who heads the Security and Protection Force at the Interior Ministry, told Human Rights Watch that since 2006 al-Dalu had been in a unit responsible for protecting Gaza government officials and visiting dignitaries. Major al-Wali said that al-Dalu had worked every day during the latest fighting, and that he was not a member of any armed group.

Police spokesman Ayman al-Batnigri also told Human Rights Watch that al-Dalu was a member of the Security and Protection Force, which he called a purely “civilian department.” In the Interior Ministry, Human Rights Watch saw a poster with 25 policemen who were killed in the November fighting that included Mohamed al-Dalu. The circumstances of each of the policemen’s deaths are not known. Eight of the killed policemen also appear on the al-Qassem Brigades’ list of killed fighters, but not Mohamed al-Dalu. None of them appeared on the lists of killed fighters from Islamic Jihad or the Popular Resistance Committees.

Under international humanitarian law, or the laws of war, which were applicable during the November fighting in Gaza, civilians and civilian objects may not be targets of attack. Police are presumed to be civilian, and thus immune from attack, unless they are formally incorporated into the armed forces of a party to the conflict or are directly participating in the hostilities.

Israel has not provided any information to support the claim that Mohamed al-Dalu was directly participating in hostilities, Human Rights Watch said.

“Israel’s belated effort, once it could scour the list of victims, to defend the attack by naming a civilian police officer found among the dead suggests an after-the-fact attempt to justify the unjustifiable,” Abrahams said.

Even if Mohamed al-Dalu were a legitimate military target, an attack on his crowded home would be unlikely to meet the requirement of proportionality, Human Rights Watch said. Under the laws of war, the expected military gain from an attack must outweigh the anticipated civilian harm.

Disproportionate attacks are serious violations which Israel has an obligation to investigate. Victims of laws of war violations and their families should be promptly and adequately compensated. Anyone responsible for deliberately or recklessly committing a serious violation of the laws of war should be prosecuted for war crimes.

“Israel needs to explain why it bombed this house filled with civilians,” Abrahams said. “Anyone who violated the law should be appropriately punished.”

The recent fighting between Israel and Hamas and armed groups in Gaza took place from November 14 to 21. It involved unlawful attacks on civilians by both sides. At least 103 Palestinian civilians and 4 Israeli civilians died during the fighting.